1. Field of the Invention
This invention relates to a weather strip for an automobile which embeds a resin made insert therein.
2. Description of the Prior Art
As illustrated in FIGS. 7 and 8, a conventional weather strip for an automobile, which comprises a main body 30 made of EPDM rubber, has a comb shaped insert 40 embedded therein in order to improve its grabbing force against a body panel and the like. Recently, inserts 40 made of resin have been used instead of metal inserts from a point of view in productivity, weight saving and the like. Such art is disclosed in, for example, Japanese Unexamined Patent Publication No. 2001-9889.
However, the conventional weather strip, which includes a main body 30 made of EPDM rubber having a comb-shaped resin insert 40 embedded therein, encounters a problem whereby a concave-convex surface (which is formed by concave portions 60 and convex portions 70) is formed on the surface thereof, thereby severely damaging its appearance.
Such problem arises because the resin made insert differs from the conventional metal made insert in its structure. That is, the metal made insert has a thickness of only 0.4 mm to 0.5 mm, whereas the resin made insert has a larger thickness ranging from 1 mm to 2 mm in order to secure its rigidity. Therefore, for the reason that the resin made insert is thicker than the conventional metal made insert, at a time EPDM rubber is injected over the resin made insert in a mold, the gaps 50 of the insert cannot be fully filled with the EPDM rubber, thereby forming considerably thinner portions on the surface over the gaps 50 compared to the rest of the surface under which the insert takes place.
It is therefore an object of this invention to provide a rubber made weather strip embedding a resin made insert which does not form a concave-convex surface on a surface of a main body of a weather strip and therefore is good in appearance.